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Quantitative Analysis of Contents of Vegetable Oils in Sesame Oils by NIRS (근적외선분광광도법을 이용한 참기름중 이종식용유지 정량법에 관한 연구)

  • Kim, Jae-Kwan;Kim, Jong-Chan;Ko, Hoan-Uck;Lee, Jung-Bock;Kim, Young-Sug;Park, Yong-Bae;Lee, Myung-Jin;Kim, Myung-Gil;Kim, Kyung-A;Park, Eun-Mi
    • Journal of Food Hygiene and Safety
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    • v.22 no.4
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    • pp.257-267
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    • 2007
  • The possibility of rapid non-destructive qualitative and quantitative analysis of vegetable oils such as perilla, com, soybean and rapaseed oils in sesame oils was evaluated. A calibration equation calculated by MPLS(Modified Partial Least Squares) regression technique was developed and coefficients of determination for perilla oil, com oil, soybean oil and rapaseed oil contents were 0.9992, 0.9694, 0.9795 and 0.9790 respectively. According to the data obtained from validation study, $R^2$ of contents of perilla, com, soybean, rapaseed oils were 0.997, 0.848, 0.957 and 0.968, and SEP of content of them 0.747, 5.069, 3.063 and 3.000 by MPLS respectively. The results indicate that the NIRS procedure can potentially be used as a non-destructive analysis method for the rapid and simple measurement of sesame oil mixed with other vegetable oils. The detection limits of the NIRS for perilla oil, com oil, soybean oil and rapaseed oil were presumed as 2%, $15{\sim}20%,\;15{\sim}20%$ and 10%, respectively.

Development and Validation of an Analytical Method for Flutianil Residue Identification Using Gas Chromatography-Electron Capture Detection (GC-ECD를 이용한 flutianil 잔류량 분석법 개발 및 확인)

  • Kwon, Ji-Eun;Do, Jung-Ah;Park, Hyejin;Lee, Ji-Young;Cho, Yoon-Jae;Oh, Jae-Ho;Rhee, Gyu-Seek;Lee, Sang-Jae;Chang, Moon-Ik
    • Korean Journal of Food Science and Technology
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    • v.46 no.1
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    • pp.7-12
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    • 2014
  • A sensitive and simple analytical method to identify flutianil residues in agricultural commodities was developed and validated using gas chromatography-electron capture detection (GC-ECD) and mass spectrometry (GC-MS). The flutianil residues were extracted with acetonitrile, partitioned with dichloromethane, and then purified using a silica solid-phase extraction (SPE) cartridge. The method was validated using pepper, sweet pepper, mandarin, hulled rice, soybean, and potato spiked with 0.02 or 0.2 mg/kg flutianil. The average recovery of flutianil was 76.5-108.0% with a relative standard deviation of less than 10%. The limit of detection and limit of quantification were 0.004 and 0.02 mg/kg, respectively. The result of recoveries and relative standard deviation were in line with Codex Alimentarius Commission Guidelines (CAC/GL 40). These results show that the method developed in this study is appropriate for flutianil identification and can be used to maintain the safety of agricultural products containing flutianil residues.

Parameter Optimization and Automation of the FLEXPART Lagrangian Particle Dispersion Model for Atmospheric Back-trajectory Analysis (공기괴 역궤적 분석을 위한 FLEXPART Lagrangian Particle Dispersion 모델의 최적화 및 자동화)

  • Kim, Jooil;Park, Sunyoung;Park, Mi-Kyung;Li, Shanlan;Kim, Jae-Yeon;Jo, Chun Ok;Kim, Ji-Yoon;Kim, Kyung-Ryul
    • Atmosphere
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    • v.23 no.1
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    • pp.93-102
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    • 2013
  • Atmospheric transport pathway of an air mass is an important constraint controlling the chemical properties of the air mass observed at a designated location. Such information could be utilized for understanding observed temporal variabilities in atmospheric concentrations of long-lived chemical compounds, of which sinks and/or sources are related particularly with natural and/or anthropogenic processes in the surface, and as well as for performing inversions to constrain the fluxes of such compounds. The Lagrangian particle dispersion model FLEXPART provides a useful tool for estimating detailed particle dispersion during atmospheric transport, a significant improvement over traditional "single-line" trajectory models that have been widely used. However, those without a modeling background seeking to create simple back-trajectory maps may find it challenging to optimize FLEXPART for their needs. In this study, we explain how to set up, operate, and optimize FLEXPART for back-trajectory analysis, and also provide automatization programs based on the open-source R language. Discussions include setting up an "AVAILABLE" file (directory of input meteorological fields stored on the computer), creating C-shell scripts for initiating FLEXPART runs and storing the output in directories designated by date, as wells as processing the FLEXPART output to create figures for a back-trajectory "footprint" (potential emission sensitivity within the boundary layer). Step by step instructions are explained for an example case of calculating back trajectories derived for Anmyeon-do, Korea for January 2011. One application is also demonstrated in interpreting observed variabilities in atmospheric $CO_2$ concentration at Anmyeon-do during this period. Back-trajectory modeling information introduced in this study should facilitate the creation and automation of most common back-trajectory calculation needs in atmospheric research.

The Influence of Calling on School Organizational Commitment of School Health Nurses (보건교사의 소명의식이 학교조직몰입에 미치는 영향)

  • Kim, Hyo Soon;Lee, Yoonshin;Kim, Ok Sun;Sok, Sohyune
    • The Journal of the Korea Contents Association
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    • v.20 no.10
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    • pp.535-543
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    • 2020
  • With the emergence of new infectious diseases and changes in the educational environment, the health problems of school-age students are increasing. Accordingly, the role of school health teachers is expanding and becoming more important. The study was to examine the effect of calling on school organizational commitment of school health nurses. Samples were a total of 143 school health nurses working in elementary, middle, and high schools, Gyeonggi-do, South Korea who understood the purpose of this study and voluntarily participated in the study. Measures were Calling and Vocation Questionnaire-Korea (CVQ-K) and organization commitmen questionnaire. Data were analyzed using SPSS/WIN 23.0 program. The analyses showed that the prediction model for school organizational commitment of school health nurses was significant (F=16.142, p<.001). The value of the adjusted R2 was 0.307, which corresponds to the explanatory power of 30.7%. The factor that was found to have the most influence on school organizational commitment of school health nurses was purpose/meaning (β=.28, p=.011), followed by number of classes (β=-.20, p=.006). In order to improve the school organizational commitment of school health nurses, the purpose/meaning and the number of classes should be considered.

Validation of an LC/MS/MS Method for the Pharmacokinetic Study of Lercanidipine (염산레르카니디핀 체내동태 연구를 위한 혈청 중 레르카니디핀의 LC/MS/MS 정량법 검증)

  • Kim, Se-Mi;Kim, Hwan-Ho;Shin, Sae-Byeok;Kang, Hyun-Ah;Yoon, Hwa;Cho, Hea-Young;Kim, Yoon-Gyoon;Yang, Chan-Woo;Yong, Chul-Soon;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.37 no.4
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    • pp.223-227
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    • 2007
  • A rapid, simple and sensitive LC/MS/MS method for the determination of lercanidipine in human serum was validated and applied to the pharmacokinetic study of lercanidipine. Lercanidipine and internal standard, amlodipine, were extracted from human serum by liquid-liquid extraction with hexan-isoamyl alcohol (100: 1, v/v) and analyzed on a $Symmetry^{(R)}$ MS $C_{18}$ column with the mobile phase of acetonitrile-0.2% aqueous formic acid (70: 30, v/v). Using MS/MS with multiple reaction monitoring (MRM) mode, lercanidipine and amlodipine were detected without severe interferences from human serum matrix. Lercanidipine produced a protonated precursor ion ($[M+H]^+$) at m/z 612.3 and a corresponding product ion at m/z 280.0. Internal standard produced a protonated precursor ion ($[M+H]^+$]) at m/z 409.0 and a corresponding product ion at m/z 238.0. The ruggedness of this method was investigated using quality control (QC) samples. This method showed linear response over the concentration range of 0.05-20 ng/mL with correlation coefficient greater than 0.999. The lower limit of quantitation using 0.5 mL of serum was 0.05 ng/mL, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the developed method ranged from 85.51 to 112.2% for lercanidipine with overall precision (% C.V.) being 3.56-13.1%. This method showed good ruggedness (within 15% C.V.) and was successfully applied for the analysis of lercanidipine in human serum samples for the pharmacokinetic studies, demonstrating the suitability of the method.

Relationship between the depth of cingulate sulcus on neonatal high resolution cranial ultrasound and gestational age (신생아 고해상 뇌 초음파검사에서 대상고랑의 깊이와 재태기간과의 관계)

  • Choi, Young Chil;Choi, Jin Yong;Lee, Jung Hwa
    • Clinical and Experimental Pediatrics
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    • v.52 no.10
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    • pp.1136-1139
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    • 2009
  • Purpose:It is critical that the exact gestational age of a newborn baby, especially premature baby, be determined to evaluate the status of a disease and its management and to estimate the prognosis of a patient. This study aimed to investigate an easy and accurate method to estimate gestational age on cranial ultrasound, requiring minimal additional time and equipment. Methods:A high-resolution coronal sonographic image was obtained via the anterior fontanel with a 5-12 Mhz linear probe after the usual cranial sonographic examination. We measured the depth of cerebral hemisphere, thickness of corpus callosum, and depth of cingulate sulcus and obtained the correlations between these factors and gestational age. Results:Depth of cingulate sulcus had the highest correlation coefficiency with gestational age (r=0.878, P=0.000). All the cases, except for 2 cases, had a gestational age of more than 37 weeks, when the depths of cingulate sulcus were more than 0.55 cm, and had a gestational age less than 34 weeks, when the depths of cingulate sulcus were less than 0.35 cm. Conclusion:Measurement of the depth of cingulate sulcus was a simple and accurate method to estimate the gestational age on cranial ultrasound. The gestational age is more than 37 weeks, when the depth of cingulate sulcus is more than 0.55 cm, and is less than 34 weeks, when the depth of cingulate sulcus is less than 0.35 cm.

Gene Transfer Optimization via E. coli-driven Conjugation in Nocardiopsis Strain Isolated via Genome Screening (유전체 스크리닝으로 선별된 Nocardiopsis 균주의 대장균 접합을 통한 유전자 도입전략 최적화)

  • Jeon, Ho-Geun;Lee, Mi-Jin;Kim, Hyun-Bum;Han, Kyu-Boem;Kim, Eung-Soo
    • Microbiology and Biotechnology Letters
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    • v.39 no.2
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    • pp.104-110
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    • 2011
  • Actinomycetes, Gram positive soil bacteria, are valuable microorganisms which produce useful secondary metabolites including antibiotics, antiparasitic substances, anti-cancer drugs, and immunosuppressants. Although a major family of actinomycetes, known as streptomycetes, has been intensively investigated at the molecular level for several decades, a potentially valuable and only recently isolated non-streptomycetes rare actinomycetes (NSRA) family has been poorly characterized due to lack of proper genetic manipulation systems. Here we report that a PCR-based genome screening strategy was performed with approximately 180 independently isolated actinomycetes strains to isolate potentially valuable NSRA strains. Thanks to this simple PCR-based genome screening strategy we were able to identify only seven NSRA strains, followed by 16S rRNA sequencing for confirmation. Through further bioassays, one potentially valuable NSRA strain (tentatively named Nocardiopsis species MMBL010) was identified which possessed both antifungal and antibacterial activities, along with the presence of polyketide synthase and non-ribosomal peptide synthase genes. Moreover, Nocardiopsis species MMBL010, which was intrinsically recalcitrant to genetic manipulation, was successfully transformed via E. coli-driven conjugation. These results suggest that PCR-based genome screening, followed by the establishment of an E. coli-driven conjugation system, is an efficient strategy to maximize potentially valuable compounds and their biosynthetic genes from NSRA strains isolated from various environments.

Rapid Determination of Ginsenosides Rb1, Rf, and Rg1 in Korean Ginseng Using HPLC (HPLC를 이용한 고려인삼 중 진세노사이드 Rb1, Rf 및 Rg1의 신속분석 방법 개발)

  • Hong, Hee-Do;Choi, Sang-Yoon;Kim, Young-Chan;Lee, Young-Chul;Cho, Chang-Won
    • Journal of Ginseng Research
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    • v.33 no.1
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    • pp.8-12
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    • 2009
  • A simple gradient HPLC method for rapid determination of major ginsenosides ($Rg_1$ and $Rb_1$) and unique ginsenoside (Rf) of Korean ginseng (Panax ginseng C.A. Meyer) was developed. Within 50min, three ginsenosides have been separated and identified on $\mu$-Bondapak $C_{18}$ column ($3.9{\times}300\;mm$, $10{\mu}m$) with gradient elution using water and acetonitrile as a mobile phase. The method was validated in terms of linearity, accuracy, and precision. The correlation coefficients ($r^2$) for calibration curves of ginsenosides were over 0.9997. The developed HPLC method was successfully applied to the analysis of ginseng samples and the recoveries of ginsenosides were in the range of $101.1{\sim}115%$ with RSD<3.2%. The developed method could be used for rapid evaluation of the ginsenosides $Rg_1$, $Rb_1$, and Rf.

Development of Simple Test Method using VOC Analyzer to Measure Volatile Organic Compounds Emission for Particleboards (VOC Analyzer를 이용한 파티클보드로부터 방산되는 휘발성유기화합물의 간이 측정방법 개발)

  • An, Jae-Yoon;Kim, Sumin;Kim, Jin-A;Kim, Hyun-Joong;Mun, Suck-Joong
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.4
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    • pp.22-30
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    • 2006
  • The volatile organic compound (VOC) Analyzer is a portable device to measure the four main aromatic hydrocarbon gases: toluene, ethylbenzene, xylene and styrene. With the VOC Analyzer, a semiconductor gas sensor eliminates the need for the carrier gas which is required for conventional gas chromatographs. In addition, since the semiconductor gas sensor is supersensitive to gas components, it is not necessary to use a conventional gas concentrator or other complicated equipment. Compared with other measurement methods, the VOC analyzer is useful for measuring toluene, ethylbenzene, xylene and styrene in wood-based panel because of its ease in obtaining field results and repeating the test. The VOC Analyzer primarily measures four VOC in the air. In this study, we designed a test method of VOC measurement for particle board. A specimen was sealed in 3L polyester bag, after 96hours we could measure maximum VOC emission level that is a stabilized VOC Value. For easy, fast and economic testing of TVOC emission from wood-based panel, we developed the test method with the VOC Analyzer. The VOC Analyzer is expected to gain widespread use in the manufacturing field where a quick and easy test for VOC emission from wood-based panel is required. Furthermore, the VOC Analyzer promises to become an easier, faster and more economic technique than the currently used standard methods.

The GR-tree: An Energy-Efficient Distributed Spatial Indexing Scheme in Wireless Sensor Networks (GR-tree: 무선 센서 네트워크에서 에너지 효율적인 분산 공간색인기법)

  • Kim, Min-Soo;Jang, In-Sung
    • Spatial Information Research
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    • v.19 no.5
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    • pp.63-74
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    • 2011
  • Recently, there has been much interest in the spatial query which energy-efficiently acquires sensor readings from sensor nodes inside specified geographical area of interests. The centralized approach which performs the spatial query at a server after acquiring all sensor readings, though simple, it incurs high wireless transmission cost in accessing all sensor nodes. In order to remove the high wireless transmission cost, various in-network spatial indexing schemes have been proposed. They have focused on reducing the transmission cost by performing distributed spatial filtering on sensor nodes. However, these in-network spatial indexing schemes have a problem which cannot optimize both the spatial filtering and the wireless routing among sensor nodes, because these schemes have been developed by simply applying the existing spatial indexing schemes into the in-network environment. Therefore, we propose a new distributed spatial indexing scheme of the GR-tree. The GR-tree which form s a MBR-based tree structure, can reduce the wireless transmission cost by optimizing both the efficient spatial filtering and the wireless routing. Finally, we compare the existing spatial indexing scheme through extensive experiments and clarify our approach's distinguished features.